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Screening for Asymptomatic Bacteriuria in Adults: an Updated Systematic Review for the U.S

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Screening for Asymptomatic Bacteriuria in Adults: an Updated Systematic Review for the U.S Evidence Synthesis Number 183 Screening for Asymptomatic Bacteriuria in Adults: An Updated Systematic Review for the U.S. Preventive Services Task Force Prepared for: Agency for Healthcare Research and Quality U.S. Department of Health and Human Services 5600 Fishers Lane Rockville, MD 20857 www.ahrq.gov Contract No. HHSA-290-2015-00007-I, Task Order No. 3 Prepared by: Kaiser Permanente Research Affiliates Evidence-based Practice Center Kaiser Permanente Center for Health Research Portland, OR Investigators: Jillian T. Henderson, PhD, MPH Elizabeth M. Webber, MS Sarah I. Bean, MPH AHRQ Publication No. 19-05252-EF-1 September 2019 This report is based on research conducted by the Kaiser Permanente Research Affiliates Evidence-based Practice Center (EPC) under contract to the Agency for Healthcare Research and Quality (AHRQ), Rockville, MD (HHSA-290-2015-00007-I, Task Order No. 3). The findings and conclusions in this document are those of the authors, who are responsible for its contents, and do not necessarily represent the views of AHRQ. Therefore, no statement in this report should be construed as an official position of AHRQ or of the U.S. Department of Health and Human Services. The information in this report is intended to help health care decision makers—patients and clinicians, health system leaders, and policymakers, among others—make well-informed decisions and thereby improve the quality of health care services. This report is not intended to be a substitute for the application of clinical judgment. Anyone who makes decisions concerning the provision of clinical care should consider this report in the same way as any medical reference and in conjunction with all other pertinent information (i.e., in the context of available resources and circumstances presented by individual patients). This report may be used, in whole or in part, as the basis for development of clinical practice guidelines and other quality enhancement tools, or as a basis for reimbursement and coverage policies. AHRQ or U.S. Department of Health and Human Services endorsement of such derivative products may not be stated or implied. Acknowledgments The authors gratefully acknowledge the following individuals for their contributions to this project: Justin Mills, MD, MPH, at AHRQ; current and former members of the U.S. Preventive Services Task Force who contributed to topic deliberations; Brandy Peaker, MD, MPH, at the Centers for Disease Control and Prevention, Andrew S. Narva, MD, Carmelle Norice-Tra, MD, PhD, and A. Gretchen Buckler, MD, MPH, at the National Institutes of Health, for providing federal partner review of the draft report; Brenda Kazemier, MD, Christine Kistler, MD, Fiona Smaill, MBChB, Lindsay Nicolle, MD, and Dimitri Drekonja, MD, who provided expert review of the draft report; Jennifer S. Lin, MD, MCR, for mentoring and project oversight; Peter Miksovsky, MD, who served as a clinical consultant during the review process; Elizabeth O’Connor, PhD, and Nadia Redmond, MS, who assisted with data analysis; Leslie Perdue, MPH, who provided technical writing assistance; Smyth Lai, MLS, who conducted literature searches; and Katherine Essick for technical and editorial assistance at the Center for Health Research. Suggested Citation Henderson JT, Webber E, Bean SI. Screening for Asymptomatic Bacteriuria in Adults: An Updated Systematic Review for the U.S. Preventive Services Task Force. Evidence Synthesis No. 183. Rockville, MD: Agency for Healthcare Research and Quality; 2019. Screening for Asymptomatic Bacteriuria ii Kaiser Permanente Research Affiliates EPC Structured Abstract Objective: To update the USPSTF’s previous recommendation statement on Screening for Asymptomatic Bacteriuria in Adults, we systematically reviewed evidence on the benefits and harms of screening for asymptomatic bacteriuria (ASB) and treatment for pregnant women, nonpregnant women, and men. Data Sources: MEDLINE, PubMed Publisher-Supplied Records, and the Cochrane Collaboration Central Registry of Controlled Trials for literature published through September 7, 2018. Study Selection: Two researchers independently reviewed 4,318 titles and abstracts and 288 full-text articles against prespecified inclusion criteria, then abstracted data from included studies. English-language randomized trials and observational studies were included to assess the direct health benefits and potential harms of screening for ASB. Randomized trials with control conditions of placebo or no treatment were included to evaluate the benefits and harms of ASB treatment, with observational studies also included for assessment of potential treatment harms among pregnant women. Included study populations were asymptomatic community-dwelling adults (ages 18+), not undergoing treatment or specialized care related to surgical or urologic procedures, including catheterization. Pregnant women of any age were also included and studied as a separate population. Due to the historical nature of the evidence, more lenient quality rating of studies was employed to allow for changes in trial reporting standards over time. Data Analysis: We synthesized data on the benefits and harms of ASB screening and treatment for general adult populations separately from studies of pregnant women. Health outcomes and harms were sparsely and inconsistently reported in the studies conducted among general adult populations and in studies of screening conducted among pregnant women, precluding meta- analysis. For these outcomes, we described findings in the review text and tables and conducted narrative synthesis. Outcomes for the treatment of screen-detected ASB in pregnancy were analyzed with random effects meta-analysis to calculate the pooled differences when data were sufficient. We examined statistical heterogeneity among the pooled studies using standard χ2 tests and estimated the proportion of total variability in point estimates using the I2 statistic. We generated funnel plots and conducted the Egger tests for small-study effects for all pooled analyses that included at least 10 studies. Using established methods, we assessed the strength of evidence for each question. Results: We included 19 studies of screening or treatment for ASB reported in 36 publications. Fourteen of the included studies were conducted among pregnant women; two of them examining the effectiveness and/or harms of screening (N=5,289) and 12 examining the effectiveness and harms of treatment (N=2,377). Five included studies examined the effectiveness and harms of treatment among adult men and nonpregnant women (N=777), with most primarily focused on women. Reporting on the characteristics of study participants was sparse in the included literature, and all but one included were judged to be fair quality in risk of bias assessments. Screening for Asymptomatic Bacteriuria iii Kaiser Permanente Research Affiliates EPC Screening: Of the two cohort studies on screening in pregnant women, one conducted in Spain (N=4,917) identified a three-fold reduction in risk for pyelonephritis in unadjusted comparisons on a retrospective unscreened and screened cohort. The other cohort study of screening in pregnant women was conducted in Turkey (N=372) and had low statistical power for comparisons of health outcomes in a screened and unscreened cohort due to rarity of outcome events. For health outcomes related to ASB screening in adult men/nonpregnant women, no eligible studies were identified for inclusion in the review. Treatment: Twelve trials of ASB treatment among pregnant women (N=2,377) and five trials of ASB treatment among general adult populations (N=777) were included. Screening with culture testing was used in all but one recent included study. Antibiotic treatment was the most common intervention, but the treatment protocols varied considerably across studies. Data from 12 trials provided evidence that treatment of ASB in pregnancy reduces the risk of pyelonephritis (pooled relative risk [RR], 0.24 [95% CI, 0.14 to 0.40], k=12, n=2,068, I2 56.9%). Seven treatment studies reported infant outcomes, demonstrating a reduction in low birthweight (<2500g or or small for gestational age [SGA; weight below the 10th percentile for gestation age]) (pooled RR, 0.64 [95% CI, 0.46 to 0.90], k=7, n=1,522, I2 15.8.6%). Data on potential harms and adverse effects of antibiotic treatment of ASB in pregnancy were sparsely reported in the trials, and power was low for observing rare outcomes. A pooled analysis from five studies reporting congenital malformations was null (pooled RR, 0.44 [95% CI, 0.16 to 1.22], k=5, n=961, I2 0%). Adverse reactions to medications were reported, including vaginitis, diarrhea, rashes, and nausea. Five trials (N=777) addressed the benefits of treating screen-detected ASB general adult populations, focused on women and older adults. Four trials were conducted only in women, and the fifth trial was primarily among older adult women (84%). Treatment was variable across the trials, ranging from a single dose to 3 months of daily antibiotics. Overall, no study found a difference in mortality, mobility, or rates of symptomatic infections between treated and untreated individuals. Data were inconsistently reported in the four studies reporting harms because they did not report any adverse events or identified few or no patients who withdrew from the study based on adverse events. Limitations: This review was limited to English-language evidence, primarily from trials conducted in high and very high HDI countries. Risk of bias was judged
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